The formation of wear resistant composites which are hard enough to function as cutting tools or which can be coated with wear resistant materials so as to function as cutting tools is known. Reference may be had, for example, to Japanese Patent Document 4-187739 published Jul. 6, 1992 and described in Patent Abstracts of Japan C-997, Oct. 21, 1992, Vol. 16, No. 509, DE 43 40 652 A1, DE 38 06 602 C2, DE 196 01 234 A1. The principle of microwave sintering as used for such composites is described in WO 96/33830.